shadow userdel: add the adaptation to the busybox ps in 01-kill_user_procs.sh

shadow userdel: add the adaptation to the busybox ps in 01-kill_user_procs.sh

In some embedded systems, users only use the ps
provided by the busybox. But the ps provided by
the busybox does not support the -eo option by
default. As a result, an error is reported when
the userdel is used. So add a judgment on ps.
If there is no ps -eo, traverse the process directly.

The error information is as follows:
 # userdel xsl
ps: invalid option -- 'e'

Signed-off-by: xiongshenglan <xiongshenglan@huawei.com>